With warmer weather comes ... Algae

CELINA - Microcystin algal toxin levels for Grand Lake are still reportedly below the threshold for no contact advisories, though officials caution lakegoers to stay away from algal blooms that look like paint spilled on the water.

Fourth of July weekend is typically one of the busiest, if not the busiest, weekend on Grand Lake, according to Grand Lake St. Marys State Park Director Dave Faler. It can be second only to Memorial Day weekend, when people are shaking off the cabin fever built up over winter - or over the course of the recent pandemic.

With more traffic expected, swimmers and boaters are advised to be mindful this weekend, as some warmer, shallower parts of the lake, including back channels, experience algal blooms.

Faler said patches of water may appear to have had paint spilled in it; these are actually patches of algae, and Faler said they can vary in color. He's received reports of blue, white, purple, black, brown and green blooms. While it might be fine to drive through the areas in a boat, people using personal watercraft such as jet skis or those dragging water tubes should steer clear, as should swimmers. If people do come into contact with the algae, they should take a shower as soon as possible, Faler said.

The north side of the lake is currently experiencing the most issues with algae, with wind pushing most of the blooms toward the northern shores and pushing it into the already warmer, shallower back channels.

The state on May 26 removed a no contact advisory on the 13,500-acre lake, making it the first time the lake has not been under a water advisory due to algal toxins since 2009.

Wright State University-Lake Campus professor Stephen Jacquemin, who studies the lake's algae said in a recent story that microcystin levels could "change on a dime," and advised people to avoid contact with obvious algal blooms.

For most of the past few years, the lake's dominant blue-green algae has been planktothrix, which gave the lake its distinctive cloudy, greenish color. What people are seeing now in the patches of blue, green and white-colored mats of algae is a combination of planktothrix, aphanizomenon and microcystis - the same three types of algae present during the bloom of 2010, Jacquemin said.

The local watershed is the only in the state designated as distressed due to unsafe algal toxin levels, a designation the watershed received in January 2011 after animals and humans were sickened by the toxins in 2010. Cyanobacteria, more commonly referred to as blue-green algae, produce a toxin called microcystin, which can cause skin rashes, respiratory and gastrointestinal distress and harm the liver, Ohio EPA officials have said.

Faler reminded people to adhere to rules for boat operation. Much like a car, people shouldn't drink and drive, and if caught, they could be charged with operating while under the influence. Personal water crafts can only be out during daylight hours, and all watercraft operators must use lifejackets. Boats should stay 300 feet from the shoreline and must follow no-wake rules.

A fireworks display is planned in the area of the Celina Moose and Eagles at 10 p.m. on Saturday, and some other private displays may happen around the lake as well. Faler said that after a fireworks barge has been put in place, a safety ring of orange balls will be set up around the barge to keep out boaters. Local law enforcement will be patrolling the area to keep the area clear.

Boaters watching the fireworks on the lake will need to have their navigation lights on, or their anchor lights on if they're not moving. Faler advised people check that their lights work properly before heading out to see the fireworks.

The state park campgrounds are booked full, and have been since two weekends before Memorial Day weekend. The parks have been busy since the pandemic, when people began to take advantage of local parks more when other events had been canceled, and Faler said his office is preparing for another busy weekend.